I'm trying to setup two PCs (one Windows, one Linux, but my understanding is that this problem is more DNS and less OS) as follows:
Home network: 192.168.1.0/24 VPN (via OpenVPN server not within the home network): 192.168.2.0/24 .
I would like a PC on both networks to be able to access three different types of site:
- Internet addresses
- Addresses on the home network
- Addresses on the vpn
However, I'm not sure how/which DNS servers to use. If I prioritize my home DNS server, I can resolve (1) and (2), but not (3). If I prioritize my VPN DNS server, I can't resolve addresses of type (2). Of course, looking up addresses via nslookup and explicitly setting the correct server works, so I know my local DNS servers are OK.
Is there any way I can set up my PCs to fallback on the second DNS server if there is no address found (NXDOMAIN)? Alternatively, is there any way I can tell different queries to go to different servers [maybe by setting up different subdomains; foo.local.something vs. bar.vpn.something]?